CN103546409B - Continuous phase QPSK (quadrature phase shift keying) modulation method and device - Google Patents
Continuous phase QPSK (quadrature phase shift keying) modulation method and device Download PDFInfo
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Abstract
The invention discloses a continuous phase QPSK (quadrature phase shift keying) modulation device. The continuous phase QPSK modulation device comprises a data change detector, a frequency selector, a carrier phase control word generator, an additional accumulated phase control word generator, a noise gate, a phase control word calculator, a phase control word accumulator and an ROM (read only memory) lookup table. The continuous phase QPSK modulation device is simple in structure and easy to implement. The invention further discloses a continuous phase QPSK modulation method. In the continuous phase QPSK modulation method, continuity of modulation waveforms is realized by smoothly transiting continuous transitional waveforms of a data waveform phase to the modulation waveforms of the current data, phase jump existing in the modulation waveforms of transmitted data before and after adjacent clocks is eliminated, and accordingly, pulse response caused by jumping phases is eliminated, symbol rate information contained in waveform signals is hidden, and communication safety and confidentiality are improved.
Description
Technical field
The present invention relates to a kind of modulator approach, particularly to a kind of quaternary phase-shift keying (PSK) of continuous phase
（Quadrature Phase Shift Keying, abbreviation QPSK）Modulator approach.
Background technology
Phase-shift keying (PSK)（Phase Shift Keying, abbreviation PSK）It is that one kind carrier phase represents input signal information
Modulation technique, transmit digital information using phase place change.Binary Phase Shift key in IS-95 and used in IMT-2000
Control（Binary Phase Shift Keying, abbreviation BPSK）, QPSK（Quadri Phase Shift
Keying, abbreviation QPSK）And offset quadraphase shift keying（Offset QPSK, abbreviation OQPSK）Modulate etc. broadly falling into phase-shift keying (PSK)
Mode.
When carrying out signal modulation using phase-shift keying (PSK) technology, phase place change is burst.In QPSK, the carrier wave letter of transmission
Number there are 4 desirable phase values, be represented by, whereinFor initial phase value, and.Therefore, when send out
When sending data to change, the carrier phase difference of adjacent transmission data is probably ± pi/2, ± π or ± 3 pi/2s.Due to phase place change
It is burst, therefore can inevitably introduce very big impulse response in SPA sudden phase anomalies point, these impulse responses are similar to punching
Sharp function（Function）, there is very strong frequency spectrum observability, considerably increase the probability that signal is trapped and demodulates.Meanwhile, phase
Position mutation can lead to system spectrum broadening, and when Bandwidth-Constrained, video stretching promotes modulated signal envelope to change.In addition, PSK pair
The linearity of amplifier is higher, and then the requirement to modulating equipment is higher, improves the cost of communication equipment.
The drawbacks described above existing for PSK modulation system, this area research worker proposes Continuous Phase Modulation
（Continuous Phase Modulation, abbreviation CPM）Modulation system.CPM modulation system is that information data is included in wink
When carrier phase or frequency on, using phase-memory act on ensure carrier phase be all continuous at any time, thus avoiding
SPA sudden phase anomalies.CPM modulation system contains the big class modulation technique that carrier phase is changed with conitnuous forms, and for example current
Minimum shift keying used in two third-generation mobile communications（Minimum Shift Keying, abbreviation MSK）, gaussian minimum shift key
Control（Gaussian Minimum Shift Keying, abbreviation GMSK）It is exactly common CPM modulation system.CPM modulation system is kept away
SPA sudden phase anomalies are exempted from, compared with PSK modulation system, CPM has more preferable spectral characteristic, and power spectrum is more concentrated；Simultaneously
The modulated signal envelope of CPM is constant, and nonlinear amplifier easy to use reduces equipment cost.But, with linear modulation phase
The concrete form of CPM signal is not only relevant with molding pulse, also with modulation index h, frequency response function pulse correlation length for ratio
The value of L is relevant, and therefore CPM modulation system is than general linear modulation（As PSK）Complexity, the realization that increased modulating equipment is multiple
Miscellaneous degree.
Content of the invention
It is an object of the invention to the asking of the SPA sudden phase anomalies that exist of PSK modulation system in the presence of overcoming prior art
Topic and the higher deficiency of CPM modulation system implementation complexity, provide a kind of continuous phase QPSK modulator approach and its modulation dress
Put, this modulator approach can overcome the shortcoming of the signal waveform that in PSK modulation system, phase hit leads to strong frequency spectrum observability, and real
Now the apparatus structure of this modulator approach is simple, and complexity is low.
In order to realize foregoing invention purpose, the invention provides technical scheme below：
A kind of continuous phase QPSK modulating device, including：
Data variation detector, for detecting that present clock sends data and adjacent previous clock transmission data whether phase
With, and unlike signal is exported according to testing result；
Frequency selector, for selecting the required carrier frequency of output modulation；
The carrier phase control word generator being connected with frequency selector, described carrier phase control word generator is used for root
Produce carrier phase control word according to selected carrier frequency；
The extra accumulated phase control word generator being connected with frequency selector, described extra accumulated phase control word occurs
Device is used for producing extra accumulated phase control word；
Gate, described gate is connected with described data variation detector and extra accumulated phase control word generator respectively
Connect, described gate is used for gating and export extra phase control word；
Phase control words computer, described phase control words computer is occurred with gate and carrier phase control word respectively
Device connects, and described phase control words computer is used for for carrier phase control word and extra phase control word carrying out addition calculation,
Obtain phase control words step-length；
The phase controlling word accumulator being connected with phase control words computer, described phase controlling word accumulator is used for phase place
Control word step-length cumulative, obtain total phase control words, this total phase control words is the address of ROM look-up table, and by this ground
R0M is delivered in location；
The depth being connected with phase controlling word accumulator is the ROM look-up table of K, and described ROM look-up table is used for storing discrete
The sinusoidal wave form value changed.
According to embodiments of the invention, described data variation detector detect present clock send data with adjacent before
One clock transmission data is identical, then output signal first signal is otherwise defeated according to the adjacent phase difference value sending between data waveform
Go out unlike signal：If phase difference value is pi/2 or -3 pi/2s, export secondary signal；If phase difference value is ± π, output the
Three signals；If phase difference value is 3 pi/2s or-pi/2, export the 4th signal.
According to embodiments of the invention, if data variation detector exports the first signal, described gate output zero control
Word processed；If data variation detector exports secondary signal, gate continuously exports M extra accumulated phase control word；If number
Export the 3rd signal according to change detector, then gate is continuous exports 2 × M extra accumulated phase control word；If data variation
Detector exports the 4th signal, then gate is continuous exports 3 × M extra accumulated phase control word, wherein, the implication of described M
For：After M clock cycle, extra accumulated phase reaches pi/2.
A kind of continuous phase QPSK modulator approach, the method is based on direct digital synthesis technique, by extra accumulated phase
Control word, is directly changed the mode of control word, is smoothly transitted into using the transition waveform with previous data waveform Phase Continuation
The modulation waveform of current data, realizes the seriality of modulation waveform, and its concrete steps includes：
Step 1：Carrier phase control word generator carrier frequency according to selected by frequency selector, produces carrier phase and controls
Word；Extra accumulated phase control word generator carrier frequency and transition waveform length M according to selected by frequency selector, produce extra
Accumulated phase control word；
Step 2：Data variation detector detects the data that the data that present clock sends is sent with adjacent previous clock
Whether identical, if identical, export the first signal, and enter step 4；Otherwise enter step 3；
Step 3：Calculate the adjacent phase difference value sending between data waveform, if phase difference value is pi/2 or -3 pi/2s, defeated
Go out secondary signal；If phase difference value is ± π, export the 3rd signal；If phase difference value is 3 pi/2s or-pi/2, output the
Four signals, enter step 4；
Step 4：Gate gates according to the output signal of data variation monitor and exports extra phase control word, if number
Output signal according to variation monitoring device is the first signal, then gate output extra phase control word is zero control word；If data
Change detector output signal is secondary signal, then gate continuously exports M extra phase control word is extra accumulated phase
Control word；If data variation detector output signal is the 3rd signal, gate 2 × M extra phase of continuous output controls
Word is extra accumulated phase control word；If data variation detector output signal is the 4th signal, the continuous output of gate 3 ×
M extra phase control word is extra accumulated phase control word；
Step 5：Carrier phase control word is added by phase control words computer with extra phase control word, obtains phase place control
Word step-length processed；
Step 6：Phase controlling word accumulator carries out phase control words step-length and adds up, and obtains total phase control words, that is, obtains
The ROM of each clock searches table address；
Step 7：The lookup table address being produced according to step 6, searches the modulation waveform signal value of present clock in ROM,
And this modulation waveform signal value is exported；
Step 8：Judge whether total phase control words of phase controlling word accumulator output reach ROM and search the table address upper limit
Value, if reaching higher limit, enters step 9；If not up to higher limit, enter step 10；
Step 9：Phase control words total in phase controlling word accumulator are reset, enters step 10；
Step 10：Judging whether run time reaches a cycle of raw modulation waveform, if reaching, terminating current number
According to modulation, if not up to, return to step 6, proceed total phase control words and add up.
According to embodiments of the invention, described in step 1, the computational methods of extra accumulated phase control word are：If through M
After the individual clock cycle, extra accumulated phase reaches pi/2, that is,, then additionally accumulated phase step-length is,
Additionally accumulated phase control word is, wherein, the implication of K is:The depth of ROM look-up table.
According to embodiments of the invention, described M value is, wherein, the implication of N is：Using N number of discrete sampling
Signal value represents the sinusoidal carrier signal of a cycle.
According to embodiments of the invention, the computational methods of carrier phase control word described in step 1 are：Assume to adoptIndividual
Discrete sample signals value represents the sinusoidal carrier signal of a cycle, then the phase contrast between two adjacent discrete sampling points is, that is, carrier phase control word be.
Compared with prior art, beneficial effects of the present invention：
1st, continuous phase QPSK modulator approach of the present invention, based on direct digital synthesis technique, by extra accumulated phase control
Word processed, directly changes the mode of control word, produces the discontinuous waveform that transition waveform replaces phase hit in traditional QPSK modulation,
Achieve the seriality of modulation waveform, before and after eliminating adjacent clock, send phase hit present in the modulation waveform of data,
Thus eliminating the impulse response producing because of SPA sudden phase anomalies, the symbol rate information containing in hidden waveshape signal, increased logical
The safety of letter and confidentiality.
2nd, continuous phase QPSK modulator approach of the present invention compared with CPM modulator approach, believe by the modulation using the inventive method
Number concrete form unrelated with the value of molding pulse, modulation index h, frequency response function pulse correlation length L, it is achieved that
The complexity of modulator approach of the present invention low it is easier to realize, modulating equipment structure is simple, low cost.
Brief description：
Fig. 1 is the structured flowchart of continuous phase QPSK modulating device of the present invention.
Fig. 2 is the FB(flow block) of continuous phase QPSK modulator approach of the present invention.
Fig. 3 (a), Fig. 3 (b) and Fig. 3 (c) are the modulating wave using continuous phase QPSK modulator approach of the present invention in embodiment
Shape figure.
When the phase contrast that Fig. 4 causes for data jump in embodiment is pi/2, traditional QPSK modulates and continuous phase of the present invention
The phase place change comparison diagram of QPSK modulation.
When the phase contrast that Fig. 5 causes for data jump in embodiment is π, traditional QPSK modulates and continuous phase of the present invention
The phase place change comparison diagram of QPSK modulation.
In figure labelling：101- data variation detector, 102- gate, 103- extra accumulated phase control word generator,
104- frequency selector, 105- carrier phase control word generator, 106- phase control words computer, 107- phase control words are tired out
Plus device, 108-ROM look-up table.
Specific embodiment
With reference to test example and specific embodiment, the present invention is described in further detail.But this should not be understood
Scope for the above-mentioned theme of the present invention is only limitted to below example, all belongs to this based on the technology that present invention is realized
The scope of invention.
Continuous phase QPSK modulator approach of the present invention is based on direct digital synthesis technique（DDS）Method is realized, first letter
Illustrate the ultimate principle producing discrete digital modulated signal using DDS.DDS generally includes 3 basic modules：Phase control words
Module, phase accumulator module and sinusoidal ROM look-up table means.Phase control words are by two neighbouring sample point phase contrast institutes really
Fixed ROM look-up table address increment；Phase accumulator is responsible for carrying out accumulating operation to phase control words, the total phase place control calculating
Word processed is that final ROM searches table address；Corresponding for input address carrier-signal amplitude value is exported by ROM look-up table, obtains
Intermediate frequency digital modulated signal.
Assume to represent the pure oscillation signal of a cycle using K discrete sample signals value, then two adjacent from
Phase contrast between scattered sampled point is, theThe value of individual sine amplitude sample signal is,.It is the minimum phase precision that DDS can reach.The pure oscillation signal value of this group sampling is deposited in advance
Enter in ROM, its address is followed successively by, K value is the depth of sine lookup table.Phase control wordsBy right
The carrier wave physical frequencies answered, system sampling frequency when realizingAnd sine lookup table depth K together decides on, its calculating
Method is：
Carrier wave physical frequenciesWith sample frequencyBetween ratio be two neighbouring sample points of carrier wave between phasetophase
Every（WithFor unit metering）, the phase accuracy that phase intervals can reach with DDS againCompare（I.e. phase intervals are removed
With phase accuracy）, you can it is calculated the ROM look-up table address increment between two neighbouring sample points of carrier wave, this value is phase
Position control word.For example, sample frequencyIt is carrier wave physical frequencies16 times when,, every 16 points of therefore DDS
The sinusoidal carrier signal of one complete cycle of output.
Embodiment 1
As shown in figure 1, continuous phase QPSK modulating device of the present invention includes data variation detector 101, frequency selector
104, carrier phase control word generator 105, extra accumulated phase control word generator 103, gate 102, phase control words
Computer 106, phase controlling word accumulator 107 and ROM look-up table 108, wherein,
Described data variation detector 101 is used for detecting that present clock sends data and sends data with adjacent previous clock
Whether identical, if data variation detector detects present clock and sends data and adjacent previous clock transmission data phase
With then output signal " 00 ", if sending, data is different, according to the different letter of the adjacent phase contrast sending between data waveform output
Number：If phase difference value is pi/2 or -3 pi/2s, output signal " 01 "；If phase difference value is ± π, output signal " 10 "；
If phase difference value is 3 pi/2s or-pi/2, output signal " 11 "；
Described frequency selector 104 is used for selecting the required carrier frequency of output modulation.
Described carrier phase control word generator 105 is connected with frequency selector 104, for according to frequency selector 104
Selected carrier frequency produces carrier phase control word.
Described extra accumulated phase control word generator 103 is connected with frequency selector 104, extra accumulated phase control word
Generator 103 is used for producing extra accumulated phase control word.
Described gate 102 is connected with data variation detector 101 and extra accumulated phase control word generator 103 respectively
Connect, gate is used for gating and export extra phase control word.If data variation detector 201 output signal is " 00 ", select
The extra phase control word of logical device 102 output is zero control word；If data variation detector 101 output signal is " 01 ", select
The M extra phase control word that logical device 102 continuously exports is extra accumulated phase control word；If data variation detector 101 is defeated
Going out signal is " 10 ", then 2 × M extra phase the control word that gate 102 continuously exports is extra accumulated phase control word；If
Data variation detector 101 output signal is " 11 ", then 3 × M extra phase the control word that gate 102 continuously exports is volume
Outer accumulated phase control word, wherein, the implication of described M is：After M clock cycle, extra accumulated phase reaches pi/2.
Described phase control words computer 106 respectively be connected gate 102 and carrier phase control word generator 105 even
Connect, phase control words computer 106 is used for for carrier phase control word and extra phase control word carrying out addition calculation, obtains phase
Position control word step-length.
Described phase controlling word accumulator 107 is connected with phase control words computer 106, phase controlling word accumulator 107
Cumulative for phase control words step-length, obtain total phase control words, this total phase control words is the ground of ROM look-up table 108
Location, and R0M is delivered in this address；
Described ROM look-up table 108 is connected with phase controlling word accumulator 107, and ROM look-up table 108 is used for storing discretization
Sinusoidal wave form value.
Embodiment 2
It should be noted that K represents the depth of ROM look-up table, that is, ROM searches the higher limit of table address.
It should be noted that in the present embodiment, M represents：After M clock cycle, extra accumulated phase reaches pi/2, M
Also illustrate that the fundamental length of excessive waveform.When phase contrast is for pi/2 or -3 pi/2, after M clock cycle excessive waveform with work as
The modulation waveform of front data is in smoothing junction；When phase contrast is ± π, excessive waveform and current number after 2 × M clock cycle
According to modulation waveform in smoothing junction；When phase contrast is 3 pi/2s or during-pi/2, excessive waveform and ought after 3 × M clock cycle
The modulation waveform of front data is in smoothing junction.
The fundamental length of excessive waveform can also be represented with M1, that is, extra accumulated phase reaches after M1 clock cycle
π.So, when phase contrast is for pi/2 or -3 pi/2, the modulating wave of excessive waveform and current data after M1/2 clock cycle
Shape is in smoothing junction；When phase contrast is ± π, after M1 clock cycle, excessive waveform and the modulation waveform of current data smooth
Connect；When phase contrast is 3 pi/2s or-pi/2, the modulating wave of excessive waveform and current data after 3 × M1/2 clock cycle
Shape is in smoothing junction.Likewise, the fundamental length of excessive waveform can be represented with M2, additionally add up after M2 clock cycle
Phase place reaches 3 pi/2s.So, when phase contrast is for pi/2 or -3 pi/2, excessive waveform and current number after M2/3 clock cycle
According to modulation waveform in smoothing junction；When phase contrast is ± π, excessive waveform and current number after 2 × M2/3 clock cycle
According to modulation waveform in smoothing junction；When phase contrast is 3 pi/2s or during-pi/2, excessive waveform and currently after M2 clock cycle
The modulation waveform of data is in smoothing junction.
M and N does not have proportionate relationship, and M can take arbitrary value, in the present embodiment, takes, N represents：Using N number of discrete
Sampled signal values represent the sinusoidal carrier signal of a cycle.
With reference to Fig. 2, when traditional QPSK modulates, if two adjacent data differences, modulation waveform can produce ± pi/2 or ± π
Or ± 3 pi/2 degree phase hit point.Continuous phase QPSK modulator approach of the present invention by extra accumulated phase control word, directly
Change the mode of phase control words, be smoothly transitted into current data using the transition waveform with previous data waveform Phase Continuation
Modulation waveform, that is, utilize this transition waveform to replace the discontinuous waveform of phase hit in traditional QPSK modulation, realize modulating wave
The seriality of shape, its concrete steps includes：
Step 201：Carrier phase control word generator carrier frequency according to selected by frequency selector, produces carrier phase control
Word processed；Extra accumulated phase control word generator carrier frequency and transition waveform length M according to selected by frequency selector, produce volume
Outer accumulated phase control word；
Assume that extra accumulated phase reaches pi/2, that is, after M clock, i.e. extra accumulated phase step-length
For, then extra accumulated phase control word；Assume to adoptIndividual discrete sample signals value represents one
The sinusoidal carrier signal in cycle, then the phase contrast between two adjacent discrete carrier sampled points be, i.e. carrier wave
Phase step is, then carrier phase control word be.
In the present embodiment, K value 128, N value for 16, M value is, then additionally accumulated phase step-length is, extra accumulated phase control word, carrier phase step-length is, carry
Wave phase control word is.
Step 202：Data variation detector detects the number that the data that present clock sends is sent with adjacent previous clock
According to whether identical, if identical, output signal " 00 ", and enter step 204, if it is different, then entering step 203.
Step 203：Calculate the adjacent phase difference value sending between data carrier waveform, before that is, the phase value of current data deducts
The phase value of one data, so that it is determined that gating time length, data variation detector exports different further according to gating time length
Signal：If phase difference value is pi/2 or -3 pi/2s, output signal " 01 "；If phase difference value is ± π, output signal
“10”；If phase difference value is 3 pi/2s or-pi/2, output signal " 11 " enters step 204.
Step 204：Gate gates according to the output signal of data variation detector and exports extra phase control word, if
The output signal of data variation detector is " 00 ", then gate output extra phase control word is zero control word；If data becomes
Changing detector output signal is " 01 ", then gate continuously exports M（M=4）Individual extra phase control word is extra accumulated phase control
Word processed, i.e. continuous 4 clocks extra accumulated phase control word of output；If data variation detector output signal is " 10 ", select
2 × M=8 extra phase control word of the continuous output of logical device is extra accumulated phase control word；If data variation detector output letter
Number it is " 11 ", then 3 × M=12 extra phase control word of the continuous output of gate is extra accumulated phase control word.
Step 205：Carrier phase control word is added by phase control words computer with extra phase control word, obtains phase place
Control word step-length.In the present embodiment, when the output signal of data variation detector is " 00 ", phase control words step-length is carrier wave
Phase control words, corresponding phase step is carrier phase step-length；When data variation detector exports letter
Number for " 01 " or " 10 " or " 11 " when, phase control words step-length be carrier phase control wordWith extra phase control word
Sum, that is,, corresponding phase step is carrier phase step-length and extra accumulated phase step-length sum, is.
Step 206：Phase controlling word accumulator carries out phase control words step-length and adds up, and obtains total phase control words, that is, often
The ROM of one clock searches table address, and its accumulation calculating method is：Phase controlling word accumulator is new by produce after a upper clock
Total phase control words feed back to the input of itself, next clock continue be added with phase control words step-length, be somebody's turn to do
Total phase control words of clock, this total phase control words is that the ROM in this moment searches table address, and ROM is as modulating wave for input
The address of tabling look-up of shape.
Step 207：The lookup table address being produced according to step 206, searches the modulation waveform signal of present clock in ROM
Value, and this modulation waveform signal value is exported.
Step 208：Judge whether total phase control words of phase controlling word accumulator output reach the higher limit of setting, this
In embodiment, that is, judging whether total phase control words reach 128, if reaching 128, entering step 209；If not up to 128,
Enter step 210.
Step 209：Phase control words total in phase controlling word accumulator are reset, enters step 210.
Step 210：Judging whether run time reaches a cycle of raw modulation waveform, if reaching, terminating current
The modulation of data, if not up to, return to step 206, proceed total phase control words and add up.
With reference to Fig. 3 (a), Fig. 3 (b) and Fig. 3 (c) it is assumed that once transmission data changes when modulating signal phase is 4 π,
For example, shown in Fig. 3 (a), traditional QPSK modulation waveform（Dotted line waveform in Fig. 3 (a)）Phase place have a size be pi/2 jump
Become, as shown in A point in Fig. 3 (a)；Again for example, shown in Fig. 3 (b), traditional QPSK modulation waveform（Dotted line waveform in Fig. 3 (b)）
Phase place have a size be π saltus step, as shown in B point in Fig. 3 (b)；Again for example, shown in Fig. 3 (c), traditional QPSK modulation
Waveform（Dotted line waveform in Fig. 3 (c)）Phase place have the saltus step that a size is 3 pi/2s, as shown in C point in Fig. 3 (c).Using this
Invention continuous phase QPSK modulator approach, then utilize the fast transition waveform with previous data waveform Phase Continuation（Fig. 3 (a)
Middle phase place is that in solid line waveform or Fig. 3 (b) between 4 π to 4.5 π, phase place is in solid line waveform or Fig. 3 (c) between 4 π to 5 π
Phase place is the solid line waveform between 4 π to 5.5 π）It is smoothly transitted into the modulation waveform of current data, thus hiding symbol trip point
Information, reduces the high fdrequency components of SPA sudden phase anomalies point.2 π periodic characteristics according to pure oscillation signal phase are it is known that Fig. 3
(a), Fig. 3 (b) and Fig. 3 (c) be also respectively phase contrast size be -3 pi/2s,-π and situation during-pi/2, that is, phase contrast be pi/2 and -
The waveform of 3 pi/2s is consistent, and phase contrast is that π is consistent with the waveform of-π, and it is consistent with the waveform of-pi/2 that phase contrast is 3 pi/2s.
With reference to Fig. 4 it is assumed that k1Total phase control words in+1 moment are 112, and signal phase is.In k1+ 3 and k1+
The change of once transmission data between 4 clocks, the corresponding phase difference value of this change is pi/2.Carrier wave shown in secondary series in Fig. 4
Phase place is continuous.In k1+ 1 to k1During+3 clocks, the total phase control words under the inventive method are increased with step-length 8, corresponding tune
Waveform phase processed is with step-lengthChange, modulation waveform phase place is consistent with the phase place of traditional QPSK modulation waveform.In k1When+3
Clock, in phase controlling word accumulator, master control word has reached higher limit 128（Phase value reaches 2 π）, so phase control words are tired out
Plus total phase control words reset in device.k1+ 4 clocks are to k1Between+7 clocks, in Fig. 4 the 4th row, traditional QPSK modulation waveform is total
Phase control words are because of k1The data variation of+4 clocks and produce the saltus step of pi/2, be changed into 40 from 8, extra address increment be K/4=32,
Corresponding modulating waveform phase fromJump to, the total phase control words of remaining clock still increase by step-length 8, modulation waveform phase
Step-length is pressed in positionIncrease.And the modulation waveform under modulator approach of the present invention does not occur obvious phase hit, but with 16 phase
Position control word step-length, that is,Phase step " pursuit " tradition QPSK modulation in waveform phase.In k1+ 4 clocks, phase place control
In word accumulator processed, total phase control words are 16, and corresponding modulation waveform phase place is, in k1+ 5 clocks, phase control words are tired out
Plus total phase control words are 32 in device, corresponding modulation waveform phase place is.To k1+ 7 clocks, under modulator approach of the present invention
Identical under always phase control words are modulated with traditional QPSK with modulation waveform phase place, the then extra phase control of gate output
Word vanishing processed, phase control words step-length revert to carrier phase control word 8, completes to smooth even with the modulation waveform of current data
Connect.
With reference to Fig. 5 it is assumed that k2Total phase control words in+1 moment are 112, and signal phase is.In k2+ 3 and k2+
The change of once transmission data between 4 clocks, the corresponding phase difference value of this change is π.Carrier wave phase shown in secondary series in Fig. 5
Position is continuous.In k2+ 1 to k2During+3 clocks, the total phase control words under the inventive method are increased with step-length 8, corresponding modulating
Waveform phase is with step-lengthChange, modulation waveform phase place is consistent with the phase place of traditional QPSK modulation waveform.In k2+ 3 clocks,
In phase controlling word accumulator, master control word has reached higher limit 128（Phase value reaches 2 π）, so phase control words add up
In device, total phase control words reset.k2+ 4 clocks are to k2Between+11 clocks, total phase of traditional QPSK modulation waveform in Fig. 5 the 4th row
Position control word is because of k2The data polarity of+4 clocks inverts and saltus step occurs, and is changed into 72 from 8, and extra address increment is K/2=64, right
Answer modulation waveform phase place fromJump to, the total phase control words of remaining clock still increase by step-length 8, modulation waveform phase place
By step-lengthIncrease.And the modulation waveform under modulator approach of the present invention does not occur phase hit, but with 16 phase control words
Step-length, that is,Phase step " pursuit " tradition QPSK modulation in waveform phase.In k2+ 4 clocks, phase control words add up
In device, total phase control words are 16, and corresponding modulation waveform phase place is, in k2+ 5 clocks, total in phase controlling word accumulator
Phase control words are 32, and corresponding modulation waveform phase place is.To k2+ 11 clocks, the total phase place control under modulator approach of the present invention
Lower with traditional QPSK modulation identical, the extra accumulated phase control word that then gate exports of word processed and modulation waveform phase place
Vanishing, phase control words step-length revert to carrier phase control word 8, completes in smoothing junction with the modulation waveform of current data.
k2During+11 clock, in phase controlling word accumulator, total phase control words have reached higher limit 128, so phase control words add up
In device, total phase control words reset.k2+ 11 clocks and k2Between+12 clocks, transmission data is not changed in, the control word of modulation waveform
With step-length 8, phase place is with step-lengthContinue change, so, in k2During+12 clock, total phase controlling in phase controlling word accumulator
Word is 8, and carrier phase is.
The phase contrast that data variation causes is that during -3 pi/2, modulation waveform phase place change and phase contrast are the phase place change of pi/2
Unanimously, phase contrast is that during-π, modulation waveform phase place change is consistent with the phase place change that phase contrast is π, is not repeating herein.
Likewise, when the phase contrast that causes of data variation is 3 pi/2, the modulation waveform phase place under the inventive method is with 16
Phase control words step-length,Phase step " pursuit " tradition QPSK modulation in waveform phase, until complete and current data
Modulation waveform in smoothing junction.Phase contrast is-pi/2 when modulation waveform phase place change consistent with the phase place change of 3 pi/2s, herein not
Repeating.
Continuous phase QPSK modulator approach of the present invention, based on direct digital synthesis technique, is controlled by extra accumulated phase
Word, directly changes the mode of control word, produces the discontinuous waveform that transition waveform replaces phase hit in traditional QPSK modulation, real
Show the seriality of modulation waveform, before and after eliminating adjacent clock, send phase hit present in the modulation waveform of data, from
And eliminate the impulse response producing because of SPA sudden phase anomalies, and the symbol rate information containing in hidden waveshape signal, increased communication
Safety and confidentiality, this modulator approach and device are applied to the military wireless communication system of anti-intercepting and capturing, or civilian arrowband is wireless
Communication system.
Continuous phase QPSK modulator approach of the present invention compared with CPM modulator approach, using the modulated signal of the inventive method
Concrete form unrelated with the value of molding pulse, modulation index h, frequency response function pulse correlation length L, it is achieved that this
The complexity of invention modulator approach low it is easier to realize, modulating equipment structure is simple, low cost.
Claims (7)
1. a kind of continuous phase QPSK modulating device is it is characterised in that this modulating device includes：
Data variation detector, whether identical for detecting present clock transmission data and adjacent previous clock transmission data,
And according to the adjacent phase difference value sending between data waveform output unlike signal；
Frequency selector, for selecting the required carrier frequency of output modulation；
The carrier phase control word generator being connected with frequency selector, described carrier phase control word generator is used for according to institute
Carrier frequency is selected to produce carrier phase control word；
The extra accumulated phase control word generator being connected with frequency selector, described extra accumulated phase control word generator is used
In carrier frequency according to selected by described frequency selector and transition waveform length M with previous data waveform Phase Continuation, produce
Raw extra accumulated phase control word；Wherein, M represents that extra accumulated phase reaches pi/2 after M clock cycle, also illustrates that
The fundamental length of degree waveform；
Gate, described gate is connected with described data variation detector and extra accumulated phase control word generator respectively,
Described gate is used for the output signal according to described data variation detector, gates and export the phase that additionally adds up of respective amount
Position control word；
Phase control words computer, described phase control words computer is connected with gate and carrier phase control word generator respectively
Connect, described phase control words computer is used for for carrier phase control word and extra accumulated phase control word carrying out addition calculation,
Obtain phase control words step-length；
The phase controlling word accumulator being connected with phase control words computer, described phase controlling word accumulator is used for phase controlling
Adding up of word step-length, obtains total phase control words, this total phase control words is the address of ROM look-up table, and this address is sent
To ROM；
The depth being connected with phase controlling word accumulator is the ROM look-up table of K, and described ROM look-up table is used for storing discretization
Sinusoidal wave form value.
2. continuous phase QPSK modulating device according to claim 1 is it is characterised in that described data variation detector is examined
Measure present clock transmission data identical with adjacent previous clock transmission data, then export the first signal, otherwise according to adjacent
Send the phase difference value output unlike signal between data waveform：If phase difference value is pi/2 or -3 pi/2s, export secondary signal；
If phase difference value is ± π, export the 3rd signal；If phase difference value is 3 pi/2s or-pi/2, export the 4th signal.
If 3. continuous phase QPSK modulating device according to claim 2 is it is characterised in that data variation detector exports
First signal, then described gate output zero control word；If data variation detector exports secondary signal, gate is continuously defeated
Go out M extra accumulated phase control word；If data variation detector exports the 3rd signal, gate continuously exports 2 × M volume
Outer accumulated phase control word；If data variation detector exports the 4th signal, the continuous output of gate 3 × M additionally adds up
Phase control words, wherein, the implication of described M is：After M clock cycle, extra accumulated phase reaches pi/2.
4. a kind of continuous phase QPSK modulator approach is it is characterised in that the method is based on direct digital synthesis technique, by extra
Accumulated phase control word, directly changes the mode of control word, is put down using the transition waveform with previous data waveform Phase Continuation
Cunning is transitioned into the modulation waveform of current data, realizes the seriality of modulation waveform, its concrete steps includes：
Step 1：Carrier phase control word generator carrier frequency according to selected by frequency selector, produces carrier phase control word；
Step 2：It is identical with adjacent previous clock transmission data, then that data variation detector detects present clock transmission data
Export the first signal, and enter step 4；Otherwise enter step 3；
Step 3：Calculate the adjacent phase difference value sending between data waveform, if phase difference value is pi/2 or -3 pi/2s, output the
Binary signal；If phase difference value is ± π, export the 3rd signal；If phase difference value is 3 pi/2s or-pi/2, output the 4th letter
Number, enter step 4；
Step 4：Extra accumulated phase control word generator according to selected by described frequency selector carrier frequency and with previous number
According to waveform phase continuous transition waveform length M, produce extra accumulated phase control word, gate is according to data variation detector
Output signal gate and export the extra accumulated phase control word of respective amount, if the output signal of data variation detector is
First signal, then gate exports extra accumulated phase control word is zero control word；If data variation detector output signal is
Secondary signal, then gate continuously export the extra accumulated phase control word of M；If data variation detector output signal is the 3rd
Signal, then gate is continuous exports 2 × M extra accumulated phase control word；If data variation detector output signal is the 4th
Signal, then gate is continuous exports 3 × M extra accumulated phase control word；Wherein, M represents extra after M clock cycle
Accumulated phase reaches pi/2, also illustrates that the fundamental length of excessive waveform；
Step 5：Carrier phase control word is added by phase control words computer with extra accumulated phase control word, obtains phase place control
Word step-length processed；
Step 6：Phase controlling word accumulator carries out phase control words step-length and adds up, and obtains total phase control words, that is, obtains each
The ROM of clock searches table address；
Step 7：The lookup table address being produced according to step 6, searches the modulation waveform signal value of present clock in ROM, and will
This modulation waveform signal value exports；
Step 8：Judge whether total phase control words of phase controlling word accumulator output reach ROM and search table address higher limit,
If reaching higher limit, enter step 9；If not up to higher limit, enter step 10；
Step 9：Phase control words total in phase controlling word accumulator are reset, enters step 10；
Step 10：Judging whether run time reaches a cycle of raw modulation waveform, if reaching, terminating current data
Modulation, if not up to, return to step 6, proceed total phase control words and add up.
5. continuous phase QPSK modulator approach according to claim 4 is it is characterised in that additionally add up described in step 4
The computational methods of phase control words are：If extra accumulated phase reaches pi/2, that is, after M clock cycle
MΔθa=pi/2, then additionally accumulated phase step-length isAdditionally accumulated phase control word isIts
In, the implication of K is:The depth of ROM look-up table.
6. continuous phase QPSK modulator approach according to claim 5 is it is characterised in that described transition waveform length M takes
It is worth and beWherein, the implication of N is：Represent the sinusoidal carrier signal of a cycle using N number of discrete sample signals value.
7. the continuous phase QPSK modulator approach according to one of claim 4 to 6 is it is characterised in that carry described in step 1
The computational methods of wave phase control word are：The depth of the sinusoidal ROM look-up table of hypothesis is K, is represented using N number of discrete sample signals value
The sinusoidal carrier signal of a cycle, then the phase contrast between two adjacent discrete sampling points is Δ θ=2 π/N, then carrier wave phase
Position control word is CDDS=K/N.
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| 基于软件无线电的BPSK/QPSK解调器的研究;苏伟;《中国优秀硕士学位论文全文数据库》;20081130;全文 * |
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